diff --git a/bpython/importcompletion.py b/bpython/importcompletion.py
@@ -66,6 +66,7 @@ def __init__(
            skiplist if skiplist is not None else tuple()
        )
        self.fully_loaded = False

        if paths is None:
            self.modules.update(sys.builtin_module_names)
@@ -220,6 +221,8 @@ def find_modules(
                        continue
                    if (stat.st_dev, stat.st_ino) not in self.paths:
                        self.paths.add((stat.st_dev, stat.st_ino))
                        for subname in self.find_modules(path_real):
                            if subname is None:
                                yield None  # take a break to avoid unresponsiveness
@@ -250,3 +253,33 @@ def find_coroutine(self) -> Optional[bool]:
            self.fully_loaded = True

        return True